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Sand dunes form one of the most fragile terrestrial ecosystems. In Rajasthan they have a diverse vegetation and are often utilized by considerable human and livestock populations. A thorough knowledge of the resource utilization by the human and animal populations is essential if the future potential of the ecosystem and its physical stability under changing environmental conditions are to be accurately assessed. This study examines the socio-economic aspects of land degradation at four sites in Churu and Jhunjhunu districts, northwest Rajasthan. An attempt is made to assess the socio-economic factors leading to land degradation. Data on human use of the Rajasthan (Thar) Desert semiarid ecosystem were collected through individual interviews, group discussions and field measurements. The present exploitation of soil and vegetation resources, possible future biomass deficiency, its impact on sustainable development and role in land degradation are examined.

The average number of people in each household in the study area, and the number of livestock each household maintains are too high to allow a satisfactory income to be sustained. The annual income of 50-90 per cent of households was less than 10 000 rupees ($US 1 = 17 rupees in 1987). Sale and consumption of milk, wool, surplus animals and wood provide livelihood, supplemented with income from wage labour. Rain-fed marginal land cultivation produces poor yields and the per capita production is too low to justify the huge soil erosion losses occurring. The number of goats, sheep and cattle owned by the inhabitants has increased tremendously in recent years. Stocking rates vary from 1.63 to 12.08 animals per hectare. The grazing pressure during the dry season, when forage availability decreases, reaches 34.9 animals per hectare. As a result of overgrazing, the land productivity has decreased considerably. The annual fodder deficit values in the study area are enormous. Demand for fuelwood at all the study sites is increasing, yet available forests have already largely been cut down. The distance travelled to collect fuelwood has been increasing, whereas the amount and quality of fuelwood is decreasing. Use of cattle dung to supplement fuelwood during the summer dry season and in drought periods has been decreasing due to low fodder availability and high livestock mortality. Human numbers are increasing, and livestock numbers are also multiplying (except in drought periods) and consequently the available resources are decreasing. Soil erosion and desertification will continue to increase during the next decade unless effective counter measures are undertaken.